Compact sealed electrical relay



June 17, 1969 J. L. BECKNELL 3,451,017

COMPACT SEALED ELECTRICAL RELAY,

Filed Sept. 15, 1967 J. L. BECKNELL COMPACT SEALED ELECTRICAL RELAY June 17, 1969 Sheet Filed Sept. 15, 1967 Q J mm. I ill Q June-17, 1969 J. BECKNELL COMPACT SEALED ELECTRICAL RELAY Sheet Filed Sept. 15, 1967 United States Patent O ABSTRACT OF THE DISCLOSURE A compact electromagnetic hermetically sealed double throw relay having a rocking armature, a sealed electromagnet compartment, a separately sealed contaminant free contact compartment and coil leads passing through the armature to coil terminals.

BACKGROUND OF THE INVENTION This invention relates to the field of electromagnetically actuated switches with hermetically sealed enclosures and having rockable armatures.

In the field of electrical devices of the type herein described the pressures are for smaller size, lighter weight, greater capacity and greater reliability. At the same time the environmental conditions under which these needs must be met become more adverse. The present invention accomplishes the desired results by providing as in the exemplary described device, a four-pole, double-throw sealed relay of high reliability, ruggedness and long life within approximately a one and one-half inch cubic space.

SUMMARY OF THE INVENTION It is an object of this invention to provide a hermetically sealed relay of minimum size and weight but with high reliability, ruggedness and current carrying capacity.

It is another object of the invention to provide such a relay with a separately sealed contaminant free contact member.

It is still another object of the invention to provide such a relay with an armature structure which is arranged to conserve space and is constructed for easy assembly.

These objects are accomplished by providing a relay with a header on one side, a sealed electromagnet compartment toward the opposite side and a separate hermetically sealed contact chamber inbetween. A fiat rocking armature is placed-in the contact chamber overlying the contact means. In this arrangement the armature occupies a small space but it occupies a relatively large portion of the cross sectional area of the relay interior and thereby gives rise to problems of how to mount the armature in an easily assembled structure and how to arrange rugged insulated leads between the electromagnet and the header where the leads are connected to exteriorly extending terminal means. It must be borne in mind that the leads must be insulated within the contact chamber with materials which are non-gassing and do not produce contact contaminants. Ceramic insulators or the like are suitably contaminant free but are not flexible and are therefore not easily adaptable to the confined interior of a relay such as is hereafter described.

3,451,017 Patented June 17, 1969 In this invention a central aper-ture is provided in the flat armature. The electromagnet leads pass therethrough, insulated and supported by an insulator of ceramic material or the like. This same space accommodates a spring clip for holding an armature pivot pin. These elements and their arrangement make possible an extremely rugged, contaminant free and easily assembled structure in a very small space.

BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 1 is an exterior view of the header end of a relay embodying the present invention;

FIG. 2 is a sectional view taken on line 2-2 of FIG. 1;

FIG. 3 is a sectional view taken on line 3-3 of FIG. 1;

FIG. 4 is a sectional view taken on line 4-4 of FIG. 2; and

FIG. 5 is an exploded isometric and partially broken away view of certain elements of the device.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, there is illustrated a sealed relay having a hermetically sealed and Welded outer nonmagnetic metallic shell comprising a rectangular cupshaped lower portion 2, an upper portion 3 and a barrier 4 therebetween which divides the shell into two separate sealed compartments, the electromagnet compartment being within the lower portion 2 and the contact compartment being within the upper portion 3.

The upper end of the shell is closed by a support plate 5 which is welded at its periphery to the upper edge of portion 3. A header 6 is welded over the central aperture of support plate 5. The electrical terminals of the relay consisting of common terminals 7 through 10, power terminals 11 through 18 and coil terminals 19 and 20 are supported in and insulated from header 6 by glass seals 21. An insulating resilient gasket 22 having apertures for the electrical terminal pins is placed over the outer surface of header 6.

A mounting plate 23 is welded to the upper peripheral edge of shell portion 3 and extends outwardly from the sides of the relay. Three mounting holes 24- are formed near the edges of mounting plate 23. A locating pin 25 is riveted to mounting plate 23.

Electromagnetic means comprising twin coils 26 and 27 having parallel magnetic cores 28 and 29' are mounted within the lower sealed compartment of the relay. A magnetic tie plate 30 joins adjacent ends of cores 28 and 29 and is welded to barrier 4 to support one end of the electromagnet assembly.

Individual magnetic pole pieces 31 and 32 are fastened to the other ends of cores 28 and 29, respectively. The upper ends of pole pieces 31 and 32 pass through nonmagnetic barrier 4 into the upper contact compartment. Pole pieces 3-1 and 32 are welded to barrier 4 to support the electromagnet assembly and brazed to barrier 4 to form a hermetic seal.

Coils 26 and 27 are covered by electrical insulating material 33. Coil 26 has terminal strips 34 and 35 extending to the exterior thereof. Similarly, coil 27 has terminal strips 36 and 37. Coils 26 and 27 are connected in series 3 by welding together terminal strips 35 and 37 as shown in FIG. 2. The coils 26 and 27 are polarized in such a a manner that the magnet fluxes produced thereby are additive. The other terminal strips 34 and 36 are welded to a pair of coil leads 38 and 39, respectively.

A spaghetti type insulating material 40 covers leads 38 and 3 9 within the coil chamber.

Coil leads 38 and 39 are hermetically sealed within and insulated from ferrules 41 by glass seals 42. Ferrules 41 are welded within apertures in barrier 4. Coil leads 38 and 39. thereby pass through barrier 4 from one compartment to the other without destroying the hermetically sealed separation therebetween.

An electrical insulating sheet 43 is placed between the lower surface of portion 2 and the coils 26 and 27.

In the upper or contact compartment a pair of end frames 44 and 45, bearing a mirror image relation to one another, are welded to the upper surface of barrier 4. Oppositely positioned apertures 46 in frames 44 and 45 serve to rotatably support the ends of an armature pivot pin 47. Frames 44 and 45 also support the ends of a pair of ceramic or glass bonded mica arc barriers 48 which are oppositely facing, but otherwise identical.

A generally flat magnetic armature 49 is mounted on pivot pin 47 by means of a spring clip 50. Clip 50* has a central aperture 51 and opposed alined depending bight portions 52.

Bight portions 52 fit within an elongated central apertu-re 53 in armature 49. The edges of clip 50 overlie the upper face of armature 49 on opposite sides of aperture 53. Armature 49 is assembled to pivot pin 47 by resiliently depressing clip 50 and inserting pin 47 into bight portions 52. Upon release the spring force of clip 50 firmly holds pin 47 within a pair of alined V-shaped grooves 54 formed in the lower face of armature 49 adjacent the ends of aperture 53.

A pair of contact finger supports 55 and 56 made of glass bonded mica or the like are molded on the upper surface of armature 49 on opposite sides of aperture 53. A plurality of holes 57 (FIG. 2) are formed in armature 49 to allow the molding material of supports 55 and 56 to flow therethrough for firm attachment to armature 49.

A return compression spring 58 is positioned under one side of armature 49 and is held in place by raised portions 59 and 60 formed on armature 49 and barrier 4, respectively.

A permanent magnet 61 is positioned under the opposite end of armature 49 and held in place by two rivets 62 which are Welded to barrier 4. Both spring 58 and magnet 61 tend to hold armature 49 in its normal position as shown in FIG. 2.

A four pole, double throw contact array is supported by header 6. Normally closed stationary contacts 63 are welded to the flattened ends of the interior roughly L-shaped portions of terminals 15 through 18. Normally open stationary contacts 64 are welded on the similar ends of terminals 11 through 14. These stationary contacts are arranged within the respective recesses of arc barrier 48.

Four movable contact springs or fingers 65 are mounted at their centers to the lower ends of common terminals 7 through 10. Springs 65 have central apertures through which pass bushings 66. Washers 67 are respectively placed over the upper surfaces of springs 65, and the upper ends of bushings 66 are riveted thereover. The central apertures of bushings 66 are placed over the lower ends of terminals 7 through and welded thereto. Normally closed movable contacts 68 are welded to the ends of springs 65 and alined with normally closed stationary contacts 63. The four normally open contacts 69 are welded to the other ends of springs 65.

The upper ends of coil leads 38 and 39 pass through parallel holes in a ceramic insulator 70 and at their upper ends are welded to conductor strips 71 and 72 which are in turn welded to thelower ends of coil tcrminals 19 and 20, respectively. Insulator 70 is recessed at 75 its lower end to straddle pivot pin 47. Insulator 70 ispdsitioned within the central apertures 51 and 53 of clip 50 and armature 49, respectively. Coil leads 38 and 39 are thereby safely insulated and well supported by a nongassing insulating material as they pass through the contact chamber. Further, this arrangement permits leads 38 and 39 to be of minimum unsupported length since they pass through the center of the fiat armature 49.

FIG. 2 shows the relay in its deenergized normal position with contacts 63 and 68 closed. When electrical power is applied to coil terminals 19 and 20, pole pieces 31 and 32 become oppositely magnetically polarized and attract the adjacent end of armature 49 against the force of spring '58 and attraction of permanent magnet 61. Since springs 65 are so formed as to have a spring bias toward their open positions, contacts 68 are permitted to open. Finger support 56 at the other side of armature 49 is raised to close contacts 69 against the spring force of springs 65. Discontinuance of electrical power to terminals 19 and 20 permits the relay mechanism to return to its original position.

I claim: 1. An electromagnetically operated relay comprising: a hermetically sealed shell comprising an electromagnet compartment and an adjacent separately hermetically sealed contact compartment; j electromagnet means in said electromagnet compart-' ment; electric terminal means arranged on the side of said contact compartment opposite said electromagnet compartment, said electric terminal means including coil terminal means through which said electromagnet means is energized; electric contact means arranged in said contact compartment; and armature operated by said electromagnet means for actuating said contact means, said armature being arranged in said contact compartment between said coil terminal means and said electromagnet means and occupying a substantial portion of the cross sectional area of said contact compartment; coil lead means leading from said electromagnet means to said coil terminal means; and said armature having an aperture through which said coil lead means pass without direct contact to provide a relatively direct path for said coil lead means from said electromagnet means to said coil terminal means. 2. The invention as defined in claim 1 together with: insulating means made of rigid insulating material surrounding said coil lead means at the point said coil lead means pass through said aperture in said armature. 3. The invention as defined in claim 2 in which insulating material is a non-gassing material.

4. The invention as defined in claim 2 in which said insulating material is ceramic. 5. The invention as defined in .claim 2 in which:

there is an armature pivot pin extending across said aperture substantially perpendicular to said coil lead means; and said insulating means comprises a member with parallel apertures on opposite sides of said pin for accommodating said coil lead means and with a recess at one side for straddling said pin. 7 6. The invention as defined in claim 1 in which: there is an armature pivot pin extending from one side of said armature to the opposite side across said aperture; said armature is and said spring clip comprises oppositely extendingportions for engaging one face of said armature on opposite sides of said aperture and further comprises a central bight portion extending through said aperture to hold said pin, the spring force of said clip said fastened to said pin by a spring clip;

being eflective to hold said pin firmly in place against the opposite face of said armature.

7. The invention as defined in claim 6 in which said spring clip has a central aperture through which passes said coil lead means.

8. The invention as defined in claim 7 together with insulating means made of rigid insulating material surrounding said coil lead means at the point at which said coil lead means pass through said aperture in said clip.

9. The invention as defined in claim 8 in Which said insulating material is a non-gassing material.

10. The invention as defined in claim 8 in Which said insulating material is ceramic.

11. The invention as defined in claim 8 in which:

said armature pivot pin extends from one side of said clip to the opposite side across said aperture in said clip; and

said insulating means comprises a member with parallel apertures on opposite sides of said pins for accommodating said coil lead means and with a recess at one side for straddling said pin.

References Cited UNITED STATES PATENTS Zimmer 335125 Nelsen 335-124 Molyneux 335-125 Kenyon 335-125 Davies 335--128 15 BERNARD A. GILHEANY, Primary Examiner.

H. BROOME, Assistant Examiner. 

